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  <title>Gets the file extension</title>

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</div><hr /><div id="splfileinfo.getextension" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">SplFileInfo::getExtension</h1>
  <p class="verinfo">(PHP 5 &gt;= 5.3.6)</p><p class="refpurpose"><span class="refname">SplFileInfo::getExtension</span> &mdash; <span class="dc-title">Gets the file extension</span></p>

 </div>

 <div class="refsect1 description" id="refsect1-splfileinfo.getextension-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="modifier">public</span> <span class="type">string</span> <span class="methodname"><strong>SplFileInfo::getExtension</strong></span>
    ( <span class="methodparam">void</span>
   )</div>

  <p class="para rdfs-comment">
    Retrieves the file extension.
  </p>

 </div>


 <div class="refsect1 parameters" id="refsect1-splfileinfo.getextension-parameters">
  <h3 class="title">参数</h3>
  <p class="para">此函数没有参数。</p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-splfileinfo.getextension-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
    Returns a <span class="type"><a href="language.types.string.html" class="type string">string</a></span> containing the file extension, or an
    empty <span class="type"><a href="language.types.string.html" class="type string">string</a></span> if the file has no extension.
  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-splfileinfo.getextension-examples">
  <h3 class="title">范例</h3>
  <div class="example" id="example-3831">
   <p><strong>Example #1 <span class="function"><strong>SplFileInfo::getExtension()</strong></span> example</strong></p>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />$info&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">SplFileInfo</span><span style="color: #007700">(</span><span style="color: #DD0000">'foo.txt'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$info</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">getExtension</span><span style="color: #007700">());<br /><br /></span><span style="color: #0000BB">$info&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">SplFileInfo</span><span style="color: #007700">(</span><span style="color: #DD0000">'photo.jpg'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$info</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">getExtension</span><span style="color: #007700">());<br /><br /></span><span style="color: #0000BB">$info&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">SplFileInfo</span><span style="color: #007700">(</span><span style="color: #DD0000">'something.tar.gz'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$info</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">getExtension</span><span style="color: #007700">());<br /><br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
   </div>

   <div class="example-contents"><p>以上例程会输出：</p></div>
   <div class="example-contents screen">
<div class="cdata"><pre>
string(3) &quot;txt&quot;
string(3) &quot;jpg&quot;
string(2) &quot;gz&quot;
</pre></div>
   </div>
  </div>
 </div>


 <div class="refsect1 notes" id="refsect1-splfileinfo.getextension-notes">
  <h3 class="title">注释</h3>
  <blockquote class="note"><p><strong class="note">Note</strong>: 
   <p class="para">
    This method is only available as of PHP 5.3.6.
    Another way of getting the extension is to use the 
    <span class="function"><a href="function.pathinfo.html" class="function">pathinfo()</a></span> function.
   </p>
   <div class="example" id="example-3832">
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$extension&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">pathinfo</span><span style="color: #007700">(</span><span style="color: #0000BB">$info</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">getFilename</span><span style="color: #007700">(),&nbsp;</span><span style="color: #0000BB">PATHINFO_EXTENSION</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

   </div>
  </p></blockquote>
 </div>
 

 <div class="refsect1 seealso" id="refsect1-splfileinfo.getextension-seealso">
  <h3 class="title">参见</h3>
  <ul class="simplelist">
   <li class="member"><span class="methodname"><a href="splfileinfo.getfilename.html" class="methodname" rel="rdfs-seeAlso">SplFileInfo::getFilename()</a> - Gets the filename</span></li>
   <li class="member"><span class="methodname"><a href="splfileinfo.getbasename.html" class="methodname" rel="rdfs-seeAlso">SplFileInfo::getBasename()</a> - Gets the base name of the file</span></li>
   <li class="member"><span class="function"><a href="function.pathinfo.html" class="function" rel="rdfs-seeAlso">pathinfo()</a> - 返回文件路径的信息</span></li>
  </ul>
 </div>


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